Ukraine's main security agency says it has detained two Russian citizens wanted by Interpol, including one who allegedly was involved in the assassination of American journalist Paul Klebnikov.

The Ukrainian Security Service (SBU) said in a statement on November 18 that it had detained a Chechen native who is a Russian citizen who "participated in a number of assassinations, in particular, the editor in chief of the Russian edition of Forbes and the deputy chairman of the apparatus of the government of the Chechen Republic in 2001-2003."

Shortly after being appointed the first editor of the Russian edition of Forbes magazine, Klebnikov was attacked by armed gunmen outside his office building in Moscow in July 2004.

Authorities said the killing was a response to Klebnikov's investigative work, which included books on Russian tycoon Boris Berezovsky and Chechen rebel leader Khozh-Akhmed Nukhayev.

Prosecutors later accused Nukhayev of masterminding the crime and arrested three Chechen men for carrying out the hit.

All three men were eventually acquitted and authorities said they no longer believed Nukhayev had ordered the killing.